


A Promise Made, But Can It Be Kept?

by Undertale (YaoiWolfGirl)



Category: Undertale (Video Game)
Genre: Angst and Feels, Blood and Violence, Fluff and Humor, Mild Language, Multi, Multiple Timelines, One Shot, Other, POV Sans (Undertale), Platonic Romance, Undertale Genocide Route, Undertale Pacifist Route, Undertale Saves and Resets
Language: English
Status: Completed
Published: 2019-07-22
Updated: 2019-07-22
Packaged: 2020-07-10 15:21:00
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 9,428
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19907884
Author URL: https://archiveofourown.org/users/YaoiWolfGirl/pseuds/Undertale
Summary: Sans' POV on the happenings in Undertale. He watches as Frisk goes through the Underground, aware of the resets, but timelines seem to be blurring together. Will he be able to keep his promise; or will he strike the human down?-----I'm sure others have done this sort of thing already, but thought it was a cool concept. *shrug*Anyways; hope you all enjoy the story!





	A Promise Made, But Can It Be Kept?

**Author's Note:**

> I wanna point out; in this story Sans is aware of resets. But he cannot fully recall the details from previous runs; sort of like in the game itself. But he does seem to have moments of déjà vu; which kinda give him an idea of what possibly might've happened in other timelines. (:

Sans walked up to the large door once again; footsteps crunching in the soft snow along the path he was now so familiar with. His face held his usual lazy grin as he grew closer, and casually leaned against it with hands in his pockets. Slowly he pulled a hand out of his blue jacket, and rapt the back of his mitten covered knuckles against the large, stone door.

"knock knock," He said, loud enough to be heard on the other side, but still in his usually soft tone.

"Who is there?" came the soft, womanly reply he always received now when he came at his usual time to practice his jokes.

"cows go."

"Cows go who?" the soft voice questioned.

"no, silly. cows go moo!" Sans chuckled at his own joke.

"Haha... ha.."

He noticed instantly that something was up. Normally the lady would've laughed much harder at his horrible jokes, so he decided to bite.

"hey, uh... somethin' up?"

"I-It is nothing." The voice replied. He didn't buy it.

"c'mon, don't _kid_ me. i can tell somethin's up,"

He waited for about a minute, ready to speak again to see if she was still there, when; "..If a human were to ever come through this door. Could you please, promise me something..?"

Sans was a bit taken aback by the sudden mention of humans, with a promise request on top of it; "..i guess it'd depend what it is."

"Please. Watch over them, and protect them," he could tell by the sound of her voice that she was serious, maybe even desperate. "Will you not?"

He stood there at the door for what seemed quite a while, when finally; "i... i promise."

Sans was not entirely sure what he'd just gotten himself into. But he felt as though he possibly made a mistake by promising this lady, who he barely knew, something that big.

* * *

A few weeks had passed by since that time, which seemed so long ago now, that he had made that promise to the older woman beyond the door. He still couldn't shake the feeling that he probably shouldn't have done such a thing, but there was no going back now. He decided to shrug it off. Besides; there was little to no chance of a human coming through anytime soon. It'd been a few years since the last one had fallen into the Underground, and everyone was sure that another wasn't going to ever fall in. It would be a little too lucky on every Monster's behalf, that a seventh and final human would ever fall down to the Underground.

Sans was very skeptical on this happening, more so compared to most other monsters.

It would probably explain his super low HP.

He sighed; a puff of warm air billowing in front of him, mixing with the frosty air. He was now on his way back to the door; the memory still at the front of his mind. He was so caught up in his thoughts while walking along the path, that he almost didn't notice something coming towards him. _Almost._

Sans instantly slipped through one of his shortcuts, transporting himself into the treeline just out of sight, and watched with narrowed eyesockets.

The thing walking down along the path came into view. Brown hair; cut into a short bob with bangs, a blue sweater with lavender stripes, dark shorts with black tights underneath them, and brown boots that came up to mid-calf.

Instantly he recognized the creature. A human.

Sans' left eye began to glow softly as his magic flared. But then he stopped. His mind instantly went back to that memory, still fresh in his mind as if it'd happened only moments ago. Sans let his magic die back down, sighing, as he let the human pass by without even knowing of his existence.

After the human got a good distance from him, he left the treeline and began to follow them.

He watched the small human (a child maybe?) step over a large branch on the ground and continue down the path. He followed; but instead of stepping over it himself, he snapped it with a quick step before vanishing himself to the treeline once more.

Suddenly his vision swam.

He saw as the human had spun around; a worried expression on their face as they saw the now broken branch, before hurriedly continuing down the path.

But... was that true? Had they actually turned around?

He could faintly recall seeing them just continue walking; as if the snap of the branch hadn't bothered them one bit.

No. He was just tired from the lack of sleep he's had since that fateful day he made the promise. That was it.

It _had_ to be it.

Brushing aside the weird feeling of déjà vu, he continued to follow the child through the snowy forest. This time he stayed behind them for quite a while, he could see the child looking around the forest as though frightened from how quiet it was. He was so distracted over his thoughts, he hadn't noticed that he'd gotten close enough that his footsteps within the snow could now be heard by the human.

Before they had the chance to turn around completely, Sans transported himself out of sight once again. The human gazed around the path with a worried expression, before continuing onward, this time a little faster than before.

Sans continued his pursuit, following the child through the snow until finally they seemed to have reached the bridge. Before they could go any further he called out.

"H u m a n."

Sans saw them freeze as he spoke to them.

"D o n ' t Y o u K n o w H o w To G r e e t A N e w P a l?" he continued. "T u r n A r o u n d A n d S h a k e M y H a n d."

The skeleton could tell that the human was afraid, by the way they slowly turned to face him and held out a shaking hand. They slowly took ahold of his hand.

And then...

_Pffffffttttttt..tt..rrrrr......_

Sans couldn't help but chuckle at his own dumb prank, and the look on the humans face wasn't too bad neither.

"heh, the ol' whoopee cushion in the hand trick;" he stated with a grin, "it's _always_ funny."

His attempt to relax the human seemed to work a bit, if their small smile was any indication of that.

Or... had they given him an emotionless stare? No. There was definitely a smile.

"anyways, you're a human right?" Sans continued without letting the human say anything. "that's hilarious. i'm sans. sans the skeleton."

The human silently smiled, allowing Sans to continue with his introduction.

"i'm actually supposed to be on the watch for humans. buuut... i don't really care about capturing anybody." Sans winked one of his eyesockets at the human, lazy grin still in place. "now my brother, papyrus, he's a human-hunting fanatic. i actually think that's him over there, let's go through the gate. my brother made the bars too wide to stop anyone."

Sans led the human across the bridge to where his sentry station sat within the snowy forest; an oddly human-shaped lamp on the ground beside it.

"quick, go hide behind that conveniently shaped lamp."

The lazy skeleton watched the human. For a second, he wasn't sure they were going to do as he instructed. His brows furrowed before he blinked and saw as they moved and quickly hid out of sight. He quickly switched back to his lazy-grin expression, hands in his pockets, just as his brother came into view.

"SANS!"

"'sup, bro?"

"YOU KNOW WHAT'S SUP, BROTHER!" Papyrus yelled at him, "IT'S BEEN EIGHT DAYS, AND YOU STILL HAVEN'T RE-CALIBRATED YOUR PUZZLES! WHAT ARE YOU DOING ANYWAYS?"

"starin' at this lamp, it's pretty cool. wanna look?" Sans couldn't help but pick on his brother.

"NO! I DON'T HAVE TIME FOR THAT!" The much taller skeleton brother scolded.

Sans listened as he went on this large spiel about needing to be ready in case a human came through, so that he'd be able to capture them and become apart of the Royal Guard. It honestly made him smile, how his younger brother had a huge strive to become popular with the other Monsters in the Underground. He was so innocent.

"hmm. maybe this lamp will help you." Sans, once again, stated.

"YOU ARE NOT HELPING, SANS! YOU LAZYBONES!" Papyrus seemed to be more riled up this time after the shorter skeleton mentioned the lamp to him. "ALL YOU DO IS SIT AROUND A BOONDOGGLE. YOU GET LAZIER AND LAZIER EVERYDAY!"

"hey, take it easy," Sans said, not being able to hide his grin. "i got a _ton_ of work done today. a skele _-ton_!"

Papyrus groaned loudly with irritation from the horrid pun that Sans had made. "SANS!!"

"come on. you're smiling"

"I AM, AND I HATE IT", Papyrus sighed. "WHY DOES SOMEONE AS GREAT AS ME, HAVE TO DO SO MUCH JUST TO GET SOME RECOGNITION?"

"man, sounds like you're really workin' yourself," Sans winked an eyesocket, " _down to the bone!_ "

Papyrus groaned once more. "I AM GOING TO ATTEND TO MY PUZZLES. AS FOR YOUR WORK... PUT A LITTLE MORE _BACKBONE_ INTO IT! NYEHEHEHEH!!!"

And with that Sans watched as his brother ran off to work on his puzzles that were up ahead. He chuckled before looking towards the lamp once more.

"ok, you can come out now."

Slowly the human came out from behind the lamp, and the short skeleton could tell that they'd been holding back laughter from listening to the bickering between the skeleton brothers. He grinned at them, but a thought crossed his mind before they could start to actually leave.

"hey. i hate to bother ya... but can ya do me a favor?" Sans watched as the human stopped and looked back at him, curiosity on their face. "my brother has been kinda down lately, and seein' a human might just make his day."

He could tell they were a little skeptical.

"don't worry, he's not dangerous, even if he tries to be." The lazy skeleton assured the child, and eventually they gave him a nod. "thanks a million. i'll be up ahead."

With that he turned around, walking back the way he came as the human continued down the path.

He looked back and frowned a bit. Sans for some reason could picture a different scenario. One where the child had not hid from his brother, and had given him creepy, emotionless stares instead of soft smiles and giggles. Red, unblinking eyes instead of soft brown that mostly stayed downcast.

He shook his head, clearing it of the thought. That wasn't what had happened. The kid was normal, everything was fine.

Or... at least he hoped it was.

* * *

As time went on, Sans continued to keep an eye on the kid, who he learned was named Frisk. Sans could tell from watching them, that Frisk was a very timid child. The kid had either ran away from the monsters who tried to fight them, or talked to them until they backed down on their own. Honestly, the kid was really sweet. With hands in his pockets, he had watched as the kid went through all of Papyrus' puzzles with little to no trouble. Mostly due to the fact that his brother accidentally gave away most the answers to them anyways.

The lazy skeleton cracked jokes here and there along the way, lightening the mood for everyone, and even getting an actual laugh from Frisk once or twice.

That was another thing. The kid was really quiet, hardly ever spoke except for soft whispers or hand motions to signal what they meant. They were just so... nice. Innocent even, just like his own brother, aside from the differences in volume to them both.

So... why did he have such an unsettling feeling from the kid at times?

Frisk hadn't done anything wrong; none that he was aware of anyways.

The short skeleton tried to ignore the nagging fear. Until he'd see something with his own eyesockets, he wasn't gonna let his doubts cloud his judgement of the human.

Instead he continued to watch Frisk along their journey. Once they reached Snowdin, he saw them buy a few items from the shop, sporting a new orange bandanna around their head afterwards. He couldn't help but chuckle a bit as it looked kinda cute on the kid.

Almost an hour had passed by the time Frisk made it through the whole town. The kid had the need to stop and talk to every Monster they met it seemed, which Sans was kinda surprised about. From the amount of Monsters that had tried to attack the kid on their way here, he was sure they'd have been more fearful. Perhaps there was more to the child than he originally thought.

Sans was still out of sight, watching them as they began to leave town. Then he stiffened.

The human's way was now blocked by his brother, and was telling the human of his insecurities, and how he still had to capture them as it was his duty. Sans had no idea why but... he had a sickening feeling in the pit of his non-existent stomach. Even so, he continued to watch the scene unfold, through the fog of the small snow storm.

His brother initiated the fight and... his eyesockets suddenly went dark.

Even though it was hard to make out anything through the fog of the storm, he could've sworn he'd seen the kid lash out at his brother. That Frisk had actually attacked Papyrus. That they had.... had...

The short skeleton brother clenched his hands into fists, magic flaring up as anger took hold of him.

But then he closed his eyes, and when he opened them again, nothing had happened. His brother's silhouette was still standing, with Frisk's a few feet away from his. The comedic skeleton blinked a couple times, to be sure he was seeing things correctly. Once he was sure, he relaxed himself, hands once again inside his pockets. But his expression stayed confused, worried even.

He had no idea why he was suddenly getting weird flashes of things like this; as though the kid had done something terrible in place of what was really happening in front of him. He shook his head, and when he looked back towards the scene, he noticed it had ended.

Papyrus made his way back to the house with Frisk in tow. Sans followed, transporting himself home to his room through one of his many shortcuts.

He listened from his room of what was going on downstairs. Even peeking out to play a incidental note of _'dun dun duunnnn...'_ with his trombone when a dog had been found in the cupboard eating all of Papyrus' extra bones.

Everything went fine. Frisk had hung out with Papyrus in his room, they had a great time from the sounds of it. His brother seemed so happy to have a new friend around. Sans couldn't help but smile at the thought, and once the kid had continued their way through the Underground towards Waterfall, he decided it was time to move on as well.

Now seated at his second sentry station, just at the entrance to Waterfall. He casually waited for the kid to arrive, while trying to think of some idea to be able to assess the kid a bit more closely now that they'd interacted with his brother enough to gain "friendship" status.

A few minutes later, Frisk appeared. Sans looked at them as they came up to his stand, giving him a curious look.

"what? haven't ya seen a guy with two jobs before?" He asked with a wink of his eyesocket. "fortunately, two jobs means twice the legally required amount of breaks. i'm headin' to Grillby's. wanna come?"

Frisk had eagerly nodded their head to him.

"well if you insist, i'll pry myself away from my work." Sans joked with the kid as he moved away from his station, walking to head further into Waterfall. "over here, i know a shortcut."

Frisk tilted their head confused, which Sans couldn't help but find to be absolutely adorable, before following the skeleton. Once around the corner, he took the kids hand, and used his magic to transport them both through one of his shortcuts. As soon as they went through, he chuckled and let go of their hand, a queasy expression on their face.

"fast shortcut, huh?" Sans asked as they walked into Grillby's, going up to the bar to sit down, saying hello to everyone as he passed by. "here, get comfy."

As they sat down, a loud noise protruded from Frisk's bar stool that caused Sans to laugh a bit.

"whoops. watch where ya sit down," he joked, "sometimes weirdos put whoopee cushions on the seats."

Frisk had a faint blush on their cheeks as they moved the gag toy from under them and sat it aside. Sans winked an eyesocket at them, lazy grin in place.

"anyway, lets order. whaddya want? fries or burger?"

The kid seemed to think it over a minute, biting their lower lip. "Um... a burger?"

"hey, that sounds pretty good," Sans agreed, "Grillbz! we'll have a double order of burg."

Frisk watched with interest as the flame Monster nodded at the skeleton, before moving to the back to make the food for them. When they turned to face Sans once more, he saw them make a very quizzical expression as they caught him "combing" his skull, before they began to laugh.

He couldn't help but laugh with them before he put the comb back into his pocket. "so, what do you think of my brother? cool right?"

Frisk nodded in response.

"of course he's cool. you would be too if you wore that outfit everyday. he'd only take it off if absolutely necessary," Sans chuckled, "oh well. at least he washes it. and by that, i mean he wears it in the shower."

Sans watched as Frisk couldn't help but softly laugh once again, hand on their stomach. The skeleton smiled. How could he ever think this kid was dangerous?

After that, Grillby brought out their food and sat it in front of them.

"ah, here comes the grub. want any ketchup?" He held up a bottle in question towards the kid.

Frisk smiled and shook their head, passing up the offer.

"oh well, more for me" Sans winked an eyesocket before tipping the bottle back and drinking from it.

Frisk watched him with wide brown eyes for a second before shrugging and turning to eat their burger. Sans, however, didn't touch his yet.

"anyways, cool or not, ya gotta agree that papyrus tries real hard." Sans continued from their previous topic. "like how he keeps tryin' to become part of the royal guard. one day, he'd gone to the house of the head of the royal guard... and begged her to let him join. she shut the door on him, since it was midnight. but when she saw him waiting there the next morning, seen his dedication, she decided to give him warrior training. it's uhh... still a work in progress."

Frisk listened to what Sans was saying as they ate, and he could tell they were actually pay attention from the way their soft brown eyes were fixed on him the whole time. He couldn't help but smile at that. Then a new thought crossed his mind.

"oh yeah, wanted to ask you somethin'" Frisk looked at him and titled their head, to indicated they were listening.

Sans turned a serious gaze on the kid now. "have you ever heard of a talking flower before?"

The kid in question, seemed to tense up slightly. Almost like they were hesitant to answer the skeleton's question. Sans waited though.

Finally, they said; "Y-yes."

Sans gave a small smirk.

"so, you know all about it. the echo flower. they're all over the marsh. say somethin' to them and they'll repeat it, over and over..." he gave a slight pause.

Frisk frowned, asking why he wanted to know.

"what about it? well, papyrus told me something interesting. he said sometimes, when no one else is around, a flower would come and whisper things to him," he began to explain, seeing how Frisk's expression seemed to change to a slightly worried one. "flattery... advice... encouragement..... predictions. weird, huh?"

Sans looked at the kid, seeing them nod slowly in agreement.

"someone must be using an echo flower to play a trick on him. keep an eye out, ok?" he asked, waiting until Frisk finally signified that they would. "thanks."

After a few more seconds, he finally hopped down from his stool.

"welp, that was a long break. i can't believe i let you pull me away from work for that long," he joked as Frisk gave him a look, crossing their arms. "heh, grillby, put the food on my tab, would ya?"

Sans began to walk away before stopping to look back, "by the way, i was gonna say somethin'. but i forgot." And with that, the skeleton left the building, transporting himself away once again before Frisk had the chance to respond.

* * *

Sans continued to watch over the kid as they went through Waterfall. He had so badly wanted to step in and help the poor kid whenever they finally encountered Undyne, but knew it would've been a bad idea. Even if he'd be able to easily handle things, he didn't wanna step on the Captain of the Royal Guard's toes. So he kept his distance, keeping to the shadows as he watched Frisk run for their life, dodging the magical spears that flew towards them.

Eventually, they escaped from the Royal Guard Captain, hiding in some of the tall marsh grass. Undyne accidentally grabbed ahold of a child Monster rather than the human themselves, thus causing her to believe they'd escaped elsewhere. After she'd left, Frisk continued their journey with Sans in tow, even if the kid was unaware of it.

Soon enough, Sans had let the human bump into him another time. He was standing by the wall, relaxed smile on his face and hands in his pockets, with a telescope beside him. When Frisk caught sight of the comedic skeleton, they beamed and happily ran up to him. He chuckled, not being able to think of how cute the kid looked when they smiled up at him.

"im thinkin' of gettin' into the telescope business," the skeleton began, "it's normally 50,000G to use this premium telescope... but, since i know ya, i'll let ya use it for free." he winked an eyesocket at them, grin still in place.

Frisk seemed to think it over, before nodding happily and moving to look through it.

Sans couldn't help but laugh when they'd pulled back and looked at him confused, a pink circle now around their eye. "heh, not satisfied, huh? don't worry. i'll give ya a full refund."

The kid huffed, not understanding why the skeleton was laughing, but soon found themselves giggling along with him.

Sans couldn't help but grin a bit more. He honestly enjoyed these moments with the kid, and stood there with his hands in his jacket pockets, lazy grin upon his face. Soon enough, the kid continued on their way and he once again stepped into the shadows to trail the kid as they went along.

He watched as they passed through Onionsan's room, actually slowing their pace down to actually listen to the poor octopus monster talk to them. He saw the kid hand an old statue an umbrella, to block out the few raindrops that were hitting it, thus giving a music box in it's lap to begin playing its soft melody correctly.

Frisk was honestly the sweetest kid that Sans had ever encountered. 

Later, the kid had once again ran into that Monster child again. Agreeing to let them share their umbrella as they walked through the rain of Waterfall. Sans was trailing behind slowly, half listening to their conversation, hood pulled up over his skull. They soon passed through the room that gave them a good view of King Asgore's castle in the distance. Sans could tell that Frisk seemed a bit hesitant once they caught sight of it, choosing to stop and look at it along with the Monster kid. Finally, they continued on.

Soon enough, Frisk ran into Undyne once more, and ran from her. Sans was worried for the kid, as he watched them run along the wooden planks. Eventually, the Royal Guard Captain had cornered the poor kid, and the short skeleton couldn't seem to look away as she destroyed the part of the planks that Frisk was standing on. It broke apart, causing them to fall down into the darkness of Waterfall's cavern.

Sans' eyesockets darkened and his hands clenched into fists.

No. The kid couldn't be dead. Not now.

He didn't want to believe it.

But.. he doubted they'd be able to survive a fall like that. They were a child after all.

Shaking his head, he used his magic to take a shortcut down to the bottom of the cavern, where the kid had fallen into. He began to search around, in knee deep water, for the kid. Soon enough, he found them, laying on a bed of golden flowers. He rushed to their side.

Sans looked over the small human, their clothes were a little dirty from the fall, and a few bumps and scrapes covered their body. But other than that, it didn't seem like they were terribly hurt from the fall. With a sigh of relieve, he moved a hand to touch the kids head, running his phalanges through their hair.

"dammit kid... really gave me a scare."

Frisk made a noise that sounded like a groan, shifting slightly, and Sans knew they were beginning to wake up.

He stood, and used his magic to teleport away once more.

* * *

As more time went on, he watched as Frisk explored more of Waterfall. Even going so far as to accept Napstablook's invitation to hangout at his place. Sans only lost track of the human one time throughout the time he'd been watching them explore. He'd kinda began to doze off while they were trying to find their way through the dimly lit area where the mushrooms and lanterns were.

When he'd awoke, he'd looked around for them before he saw them at the bottom corner of the room. He was a bit confused as to what they'd been doing there, but shrugged it off before continuing to tail them.

More time went on, they ran into Undyne again, but the Monster kid got in the way. The Royal Guard Captain had drug them off, scolding them the whole time. Sans had chuckled but continued to follow Frisk rather than worry about the consequences that the mischievous Monster child was gonna endure.

Eventually, while on a long wooden bridge, Frisk had been confronted by the Monster child. Sans watched sadly as they conversed, the Monster child telling them that he hated Frisk. But when he'd went to run off, he slipped. Sans was about to teleport himself down, to help the Monster kid, but saw that Undyne was now there. He stopped, knowing she would help him up.

But Frisk moved first, rushing out and helping the poor Monster child back up to safety. This caused him to confront Undyne, telling her not to harm his new friend.

Sans had to admit, the kid had guts.

The Royal Guard Captain hesitated before finally, she turned and left once more.

However, things didn't last long. As soon as Frisk began heading off once more, Undyne once again showed herself and confronted the human.

Sans stood by in the distance, watching their battle. It seemed just like before, with his brother. Frisk refused to fight; talking to her instead and trying to spare the Captain. However, it didn't seem to be working.

And that's when it first happened.

What exactly it was, he wasn't sure of. But one minute he was watching them battle and the next.... he was watching them once more at the start of their conversation. Undyne confronting them, and initiating the battle.

He looked around confused, before watching the scene play out before him more closely.

It seemed like Frisk somehow knew what attacks to expect from Undyne now. As if they'd experienced them before.

It then clicked. The kid had to of reset the timeline.

So... did that mean they..?

He shook his head, not wanting to think about it. Instead he continued to watch.

Frisk knew that talking and sparing would do no good after trying it last time. So, whenever Frisk was able to, they began to run away from the fish monster. Sans followed at a distance, watching over and over as Undyne ran after them, attacked them, and then ran after them again.

This continued on until finally, Hotland came into view. Sans raised a brow bone, curious to see how things would play out here in the end. Undyne hated Hotland, so he was sure the kid could escape so long as they'd make it across the border.

And that they did. Undyne, however, followed. But she seemed to be slowing down, until finally she passed out from heat exhaustion.

Frisk almost ran off but then stopped. Sans was confused until he noticed that they'd spotted something, and smirked. Of course.

It was a water station.

The comedic skeleton couldn't help but grin as he watched the kid as they got a cup of water, and poured it onto the fish monster to help hydrate her.

Undyne regained consciousness, and once she saw who had helped her, the Captain ran off back into Waterfall.

Frisk looked a little confused at that, standing there for a minute, before following.

Sans, of course, began to follow too. However, he soon stopped as another image flashed before him. A different scenario. One where the kid had fought back, leading Undyne to Hotland where they defeated her. One where they watched her melt into nothing, with a sick smile upon their face and red, emotionless eyes.

Shaking his head, he looked around.

No. That had not happened, the heat was just getting to him was all. He hurried after the kid once more.

Once caught up, he watched the hilariousness unfold before him as Frisk met up with Papyrus and went to Undyne's home. He kept his distance, knowing that the kid would be fine now. The Royal Guard Captain wouldn't be able to hurt someone who'd saved her life. Even with all the crashing and banging happening inside the house, he knew it was okay. It wasn't until the house caught fire that he began to actually worry, but then relaxed once more when he saw Undyne and Frisk leave the house. They exchanged some more words, before she left and headed to Snowdin to hang with Papyrus until her house was no longer burning.

The kid moved on, heading to Hotland once more. However, once the kid entered the Lab, he wasn't able to follow.

He sighed, a bit worried. But knew that Alphys would make sure they were safe for the time being.

So, he teleported himself away to his station that was in Hotland to wait for the human there.

* * *

Sans had taken short naps between customers at his station, selling hot dogs to those who came by. Following the kid around had really begun to tire him out. He was glad they were now with Alphys and he could take a small break, even if there was a slight nagging worry. He couldn't seem to get over the images he'd seen. But, he also didn't want to dwell on them either. Frisk was his buddy. His pal.

Frisk... was a friend to Sans.

He sighed; "dammit... get ahold of yourself sansy. everything is fine."

Movement caught his eye, and he turned to see Frisk walking towards his station. He instantly grinned.

"hey, kiddo. what's up?"

They waved to him in reply.

"heh, wanna buy a hot dog? only 30G," he asked them with a wink.

They nodded, handing him some coins.

He accepted them and gave them a hot dog. "here's your 'dog."

Suddenly, Frisk was asking for more hot dogs. Sans, being the comedian he is, decided to give them to him. But in a special sort of way.

Telling the kid to stand still, he began to give Frisk more hot dogs, placing each one atop the kids head.

Frisk giggled, but had a determined look upon their face as they stood as still as possible. Once Sans could no longer reach, he used his magic to continue to place the 'dogs atop the kids head. Eventually though, the tower of 'dogs became too much, and it toppled over. Hot dogs rained from the sky, falling all over the ground.

Both the skeleton and the human burst out into fits of laughter, enjoying their stupid idea together.

Once their laughter died down, Frisk asked for one more hot dog for the road.

"sorry bud, looks like i'm out of hot dogs." Sans said. But upon the look of disappointment on the kids face, he said; "here, have a hot cat instead."

Frisk took said hot cat and smiled brightly, before continuing on their journey through Hotland.

Sans chuckled, watching them go. He hadn't had a good laugh like that in a while, and the kid was such a good sport when it came to his jokes.

He followed them a bit more through Hotland until it came to the point once again that he was unable to. The kid really had a habit of running into that damn robot.

Oh well, he continued to move on, knowing that he'd be able to see the kid again further on.

However, it seemed each time he'd get site of the kids progress, it wouldn't be long before they ended up in another of Mettaton's damn tv show sets. Sans was beginning to grow tired of it, but continued to ignore it and move on further. Eventually, he saw the kid as they made it to L3 landing. Which means they were heading towards.... oh no.

The short skeleton brother grew worried as he realized Frisk was heading for Muffet's Parlor. He was certain the spider monster would end up eating the poor kid.

He kept an eye on things best he could without any of the spiders finding out he was watching. And to his surprise; nothing happened.

As soon as Muffet went to initiate the fight, she stopped. She almost looked... speechless.

Sans then noticed that Frisk was holding up a spider donut to her.

Heh, the damn kid was smart. Or stupidly lucky.

Either way, the spider queen let the kid pass through without any hassle. She said anyone who donates to the spider bake sale was a friend, not a foe.

However, Sans was worried. He waited a bit, to see if it would happen again. Another flash of images.

But nothing happened.

Sighing in relief, he teleported away once more, to follow the human on the rest of their journey. He was honestly happy that he didn't see any horrors this time.

It wasn't long, however, before he was cut off once more by one of Mettaton's tv sets.

Groaning in irritation, he teleported further ahead, waiting until he'd see the kid passing by again. He obviously did, eventually, but he was unsure if he wanted to continue following through Hotland or just teleport to the area he knew he'd next encounter the human.

With a shrug, he decided that's exactly what he was gonna do. So he teleported himself into the city of New Home, at MTT Resort Hotel. Once there, he leaned back against the side of the building, hands in his pockets and eyes shut as he waited.

Soon enough, he hears the small footsteps approaching him, and he opened an eyesocket to look at his friend with a lazy smile.

"hey, kiddo," he greeted, "heard your goin' to the core. how about grabbin' some dinner with me first?"

Sans could've sworn he saw the kids face flush a soft shade of red. He chuckled, brushing it off, waiting for them to respond.

"well?"

Finally, Frisk gave a small nod. "T-that sounds nice."

"great. thanks for treatin' me," he winked at the kid before turning to walk back behind the hotel, towards a wall. "over here. i know a shortcut."

Frisk tilted their head before following along. Once they got to the wall, Sans grabbed the kids hand and, once again, used his magic to open a shortcut and teleport them into the restaurant. The kid looked around, always amazed when Sans did that sort of thing. They both then went to a table and sat down.

The atmosphere was very romantic feeling. Dim lights with candles on the tables, along with a small vase that held a single rose. The waiter had asked what they wanted; Sans just ordering a burger with a bottle of ketchup. Frisk, on the other hand, ordered a steak dinner.

"well, here we are kid. guess your journey's almost over," Sans started to speak while they ate their food."you must really wanna go home."

Frisk looked up at him; a small, sad smile on their face as they nodded. Somehow, he thought maybe they were hesitant.

"hey, i know the feeling kid. though..." he paused a minute, then continued, "maybe, sometimes, its better to take what's given to you."

"..."

Sans' cheek bones began to take on a blue hue to them. "down here; you've already got food, drink, friends..." he saw the kid look down at their plate. "is what you have to do... really worth it?"

The lazy skeleton could see that Frisk didn't know how to respond. He cleared his throat.

"ah, forget it. i'm rootin' for ya, kid." He gave them a genuine smile. "hey... let me tell you a story, Frisk."

Sans then began to tell them about the promise he'd made that day, all them weeks ago. About how the womanly voice asked him to look out for and protect the next human that came through the door. When he'd finished telling them the story, he paused to look at the kids curious face.

"do you get what i'm sayin'?" Sans asked. "that promise i'd made to her... do you know what would've happened if she hadn't said anything?"

He could see the expression on Frisk's face change to one of worry.

"kiddo..." Suddenly, his eyesockets darkened. "...Y o u ' d B e D e a d W h e r e Y o u S t a n d."

He let the eye-lights return to his sockets, gaze never leaving the kids, who in turn had frozen on the spot.

"heh, lighten up, kid. i'm only jokin' with ya." His lazy grin returned. "besides. haven't i done a great job of protectin' ya? i mean, look at yourself. you haven't died a single time." He winked an eyesocket at the kid.

Frisk suddenly looked down, a look of sadness in their eyes.

"huh? what is it?"

"Actually..."

"...are you sayin' that you have?" He looked away in thought. "huh. well... at least it was only once right?"

Frisk didn't say anything.

Sans stood from the table. "heh. well.. that's all. take care of yourself, kid. 'cause someone really cares about ya."

With that, Sans left the room, heading out the same way they came in.

He didn't look back to see the kids expression.

* * *

Sans was up ahead, waiting for the kid to finish with the final battle with Mettaton. Alphys had been leading the human through the core thus far, so Sans was sure they were in safe hands. Which is why he went as far ahead as he did. All the way to the final point for them to meet along the kids journey.

His judgement hall.

He sighed, looking around the golden hallway, full of pillars, and complete with large, stained glass windows. He felt like an ass. He had no idea why he'd said those things to the kid. It hadn't even been true.

Or... had it?

When he'd first seen the human, he'd almost attacked them, sure. But would he have really killed them?

He.. didn't wanna think about it.

The short skeleton sighed, decided that a well deserved nap was just what he needed while waiting for the human to arrive. Sans leaned against a pillar, hands in his jacket pockets, and let his eyesockets close. He drifted off into a light snooze almost instantly, not having realized how tired he truly was.

After what seemed like forever, he roused to the sound of footsteps nearing the large, golden hallway.

With a yawn, he stretched before moving to stand at the center of the hall, waiting for Frisk to come to him.

The kid entered the hall, and slowly made their way towards the comedic skeleton. Sans wasn't sure if they knew it was him standing there right away or not, as they weren't really paying attention to what's in front of them. Too busy looking around the room at the windows and pillars as the kid walked.

Once they were close enough, however, they stopped and looked at him.

"so you finally made it," he began, "the end of your journey is at hand. in a few moments, you will meet the king, and the two of you will determine the fate of this world."

Frisk stared at the skeleton, a bit confused by his low voice. "Sans.. wha-"

"but that's then. now. you will be judged." His left eye flashed the faintest bit of blue magic, causing Frisk to take a step back. "you will be judged for your every action. for every EXP you've gained."

At the humans confused expression, he chuckled.

"what's EXP? it's an acronym. it stands for 'execution points'." his eyesockets darkened once more. "a way of quantifying the amount of pain you've inflicted on others. when you kill someone, your EXP increases. when you have enough EXP, your LOVE increases. LOVE is another acronym, it stands for 'level of violence'. it's a way of measuring someones capacity to hurt. the more you kill, the easier to distance yourself. the more you distance yourself, the less you will hurt. the more easily you can bring yourself to hurt others."

He took a pause, to glace over the kid. To see their sad expression. It almost looked like... regret.

Which didn't make any sense. The kid hadn't hurt anyone, he would've known if they had.

He had watched their every move.

Suddenly, a different scenario flashed before him.

_Frisk, standing before him, covered in the dust of countless Monsters. Red, crazed eyes looking at him with a sadistic smile. And in their hand, a large kitchen knife._

_He himself wore his brothers red scarf around his neck, giving the kid one final warning. To not take another step, or they would **have a bad time.**_

_The kid, however, took that next and final step._

_**"ah, well. sorry old lady,"** he heard himself saying, **"this is why i never make promises."**_

_And with that, the kid charged at him. He'd already summoned his magic, left eye flaring a brilliant cyan blue. Before the kid could even reach him, he incinerated them with one of his Gaster Blasters._

_Things then shifted, and when he opened his eyesockets, the kid was once again walking towards him._

_**"heh, that's the face of someone who's died before,"** he could hear himself say, **"guess i'm pretty good at my job, huh?"**_

_The human screamed in rage, charging at him again and swinging the knife towards Sans. He easily stepped out of the way._

_**"heh, you think i'm just gonna stand there and take it?"** he asked, holding up his hands in a shrug._

_Frisk continued to scream, slashing the knife towards the comedic skeleton, who effortlessly dodged every single time. Sometimes teleporting away if need be. He then summoned bones up from the floor, impaling the human child on them, hearing them tear through their flesh and bones._

_And once again, things shifted. He was in the middle of the room, waiting._

_Coming towards him, was Frisk._

_He just grinned as they continued the game of Cat and Mouse._

_Time and time again, he killed the human. Blood splatting the floor, cracks in the pillars. Beams of light coming from his Gaster Blasters. But they continued to come back, to charge him, and try their best to kill the short skeleton. All the while, Sans just kept on dodging their attacks. But they refused to give up._

_They were **DETERMINED.**_

_Eventually, they paused. Both panting and staring at one another._

_**"ugh... you really like swingin' that thing around huh?"** he stated, pointing towards the knife they held._

_Frisk just stood there, glaring at him._

_**"listen. i know you didn't answer me before... but,"** he paused, sighing. Then he looked them in the eyes. **"somewhere in there, i can feel it. there's a glimmer of a good person in you. the memory of someone who wanted to do the right thing. someone who, in another time, might have even been... a friend?"**_

_He watched as the kid seemed to hesitate, lowering the knife a bit._

_**"c'mon, buddy. do you remember me?"** He smiled at them. **"please, if you're listening... let's forget all about this, ok? just lay down your weapon, and.. well, my job will be a lot easier."**_

_Sans continued to watch Frisk with a guarded expression, but relaxed his stance. Showing he was sparing the kid._

_Frisk lowered their gaze, their hair blocking Sans' view of their expression. Slowly, their shoulders began to quiver, until their body was shaking. The comedic skeleton sighed, relief washing over him to see the kid backing down. He went to step forward but was stopped when he heard something._

_Laughter._

_The kid was laughing, not crying._

_It slowly built up to a manic sound, before a flash of red eyes and grinning teeth looking at him as the kid lunged._

Sans snapped back to what was in front of him, the entire scene having played before him in the fraction of a second. It was then he realized that this kid, Frisk, had been here before. In his judgement hall, to be judged for all their actions throughout the journey they had.

His eyes were dark, he could tell from the scared expression upon the kids face. Slowly, he calmed himself, and the eye lights returned to his sockets.

"...but you." Sans continued, realizing he was supposed to finish his long speech. "you never gained any LOVE."

_That's a lie._

He ignored his thoughts. That was the past. This was now.

"of 'course, that doesn't mean you're completely innocent or naive. just that you kept a certain tenderness in your heart. no matter the struggles or hardships you faced..." Frisk was watching him, slowly beginning to relax. "...you strived to do the right thing. you refused to hurt anyone. even when you ran away, you did it with a smile."

He smiled at the kid then, "you never gained LOVE. but you gained, love. does that make sense?" he chuckled, "maybe not."

The lazy skeleton paused for a minute, then continued.

"now. you're about to face the greatest challenge of your entire journey. your actions will determine the fate of this entire world. if you refuse to fight... Asgore will take your soul and destroy humanity." He watched the kids expression. "but if you kill Asgore and go home, monsters will remain trapped underground. what will you do?"

Frisk seemed to be weighing their options, not answering the skeleton before them.

"...well, if i were you, i'd have thrown in the towel by now." Sans chuckled, "but you didn't get this far by giving up, huh? that's right. you have something called 'determination'."

At the mention of their power, the human looked up at the skeleton before them.

"so long as you hold on... so long as you do what's in your heart..." He gave a smile, "i believe you can do the right thing, kid."

Frisk smiled back.

"alright. we're all countin' on ya, kid." Sans winked an eyesocket at them, "good luck."

And with that, he teleported out of the room, leaving the kid alone.

* * *

This was definitely not something that Sans expected. He thought by now the kid would've fought with Asgore, and left the Underground. But instead, Frisk had backtracked. They returned to Snowdin after receiving a call from Undyne about delivering a letter to Alphys' lab. He watched curiously as they did as was asked of them, and upon delivering said letter, things took a rather awkward turn.

Turned out that Undyne had forgotten to sign it, so the socially awkward lizard monster thought it had been the human themselves who had wrote it.

This resulted on the human and Alphys to end up going on a "date".

Sans wasn't sure why, but that bothered him a little.

Watching as things continued, eventually everything was worked out and explained properly. Undyne eventually showed up, and both women admitted to things they'd been hiding for a while. Sans honestly thought it was sweet, he was happy for his friends to finally be opening up about their feelings and such.

The kid had really helped Alphys get over her fears as well. And, the skeleton had to admit, Frisk was a very good friend indeed.

After a while, the kid went into the lab once again, and he did not follow. He didn't want to go in there unless he absolutely had to.

Eventually, they continued on their way, heading back to the castle.

Sans could only wonder why they'd had to backtrack to the lab and all that.

Shrugging it off, he let it go.

However, on his way back home, his cell beeped. He looked at it, seeing a new group message.

 _'EVERYONE! MEET FRISK AT THE CASTLE'S BARRIER!_  
_WE WILL NOT ALLOW THEM TO FIGHT EACH OTHER!' ~_ Papyrus.

His brows furrowed in confusion, wondering why his brother suddenly wanted everyone to stop the fight. Without thinking much of it, he hurriedly teleported himself to the castle. He saw that a few others, including Papyrus, had made it there before him.

"hey guys, what's up?" He said upon entry.

"That voice..." he looked over as he heard a soft woman's voice, that sounded so familiar. "Hello. I think we may.. know each other?"

"oh, hey..." He grinned. "i recognize your voice, too."

"I am Toriel. It's so nice to meet you."

He winked an eyesocket at her; "the name's sans. and, uh, same."

She then turned to introduce herself to his brother, Papyrus. He couldn't help but chuckle at his brothers response when she told a skeleton pun to him.

He looked towards the human, noticing that Frisk's eyes were scanning over everyone with a smile on their face.

Then Toriel began to speak; "My child, it seems as if you must stay here. But looking at all the great friends you have, I think you will be happy here."

Frisk smiled happily, but then Alphys turned to Papyrus.

"S-say, Papyrus, how did you know to call everyone h-here anyways?"

"LET'S JUST SAY, A LITTLE FLOWER TOLD ME!"

"A... f-flower...?"

Everyone froze as they all heared a manic, high pitched voice.

_"Y o u i d i o t s . . !"_

Suddenly, out of nowhere, a large, thorny vice suddenly grabbed Sans and the others at once. They all cried out in pain. Sans himself trying to hold onto reality, to fight back, but it was too much. Whatever this creature was, it was too powerful, even for him.

Everything soon went dark.

. . .

Reality seemed to flash in and out.

. . .

A large, horrid plant monster who had the six human souls.

. . .

Frisk fighting back with every ounce of **DETERMINATION** they had.

. . .

Sans vaguely was aware of Frisk saving him and his brother's lives.

. . . . .

After what seemed like an eternity, everything came rushing back. Slowly, Sans and the rest of the group woke up.

They were all confused, looking around for the thing, whatever it was, that had hurt them. No one could remember a thing. Sans himself could hardly recall anything but tiny flashes, and even that caused a major headache. They all turned towards Frisk, but the human was lying unconscious on the ground.

Sans jolted, and rushed to their side.

"no. no. NO." He fretted, checking the kid over for any wounds.

Don't know why he bothered. The kid was covered in them. Barely alive.

Suddenly, Toriel was at his side, a hand on his shoulder as she gently moved him aside. Moving her hands over the child's form, a bright green glow appeared. His eyes widened as he realized she was using Healing magic on the human. Slowly, the child's wounds healed to nothing but faint scars. He watched, wanting to be sure his friend was going to be okay. Eventually, her hands moved away from the kid.

"They will be alright. We just gotta let them wake up on their own."

Sans stayed by the kid, kneeling there on the ground while everyone else began looking around. They soon discovered that the barrier was now broken. Perhaps that's what caused them all to pass out? The breaking of such a strong, magical barrier. It seemed like a possibility.

At the sound of a soft groan, the shorter skeleton looked down. Frisk's eyes were opening.

He sighed in relief, glad that the kid was okay.

"frisk.." he said softly.

Soon enough, the kids eyes fully opened and they sat up. Looking around in confusion.

"Oh, you're awake." Toriel came back over towards the child. "Thank goodness."

"W-we were so worried..!" That was Alphys. "I-it felt like y-you were out forever!"

Sans stood, putting his hands into his jacket pockets.

"Yeah! Any longer and I would've freaked out!" Undyne admitted. "Tell us next time you decide to take a nap, okay?!"

The short skeleton couldn't help but chuckle.

"yeah. you made papyrus cry like a baby."

"WHAT?! I DIDN'T CRY!" the taller brother exclaimed, "I JUST CAUGHT SOMETHING IN MY EYE!"

"what did you catch?"

"TEARS!!" Papyrus sniffled loudly.

"Now, now." A deep, booming voice said. Sans looked to where the king had walked over. "The important part is that Frisk is all right. Here, Frisk. Why not drink some tea? It'll make you feel better."

The small human accepted the cup of tea from the large goat monster, sipping it slowly. Sans smiled, glad that his little buddy was alright.

"How about we all give them some space?" It was Toriel again who spoke. "They seem very exhausted. Though, I'm not sure what from."

Everyone nodded in agreement, all confused on what had actually happened. Sans didn't wanna try to think of it.

Toriel continued. "Frisk, we do not remember what exactly happened. There was a flower... and then everything went dark. And now the barrier is broken?"

Frisk seemed to tell Toriel that they didn't know either.

"Well, whenever you are ready, we will return to the surface." She smiled at the child, "Just give us the word, we'll wait here."

The human took their time to fully regain themselves, before finally turning towards all the monsters gathered by the now broken barrier.

"I'm ready."

Toriel smiled, taking the child's hand, and together they all walked up out of the Underground, and to the surface world.

Once upon the surface, they stood at the edge of the path, watching a beautiful sunset. Sans explained to his brother that the large orange thing in the sky was called 'the sun'. And soon enough, everyone was rushing down the path to head further out into the surface world.

Sans turned to look at the kid once more. "thanks, kid. for everything."

Frisk smiled at him, nodding their head in welcome. He chuckled, turning and leaving the kid with Toriel.

They were all finally free from the Underfound.

And Sans... was proud.

**Author's Note:**

> Hope this was okay! Sorry if it was a bit all over the place... been a while since I wrote anything. Heh.  
> To be honest, I should've turned this into multi-chapters buuuut.... I'm lazy.  
> Either way, hope you all enjoyed it!


End file.
